Pepper'N'Salt

philzucker wrote:

Joseph S Wisniewski wrote:

philzucker wrote:

Joseph S Wisniewski wrote:

philzucker wrote:

Salt really comes in lots of shapes and patterns out of my shaker;

The weird thing is that it doesn’t.

Common table salt is sodium chloride (NaCl) aka "halite". It forms face centered cubic crystals that are very distinctive.

The most common "salt substitute" is potassium chloride (KCl) aka "sylvite", which also forms face centered cubic crystals.

Even the less common sodium malate (Na2(C2H4O(COO)2)) forms cubic crystals.

You’ve got a lot of cuboctahedrons. Nothing edible that I can think of forms those. Very pretty, but I'd be scared to eat it.

No need to be scared, I think.

I'll give you one, maybe.

It's table salt coming out of our salt shaker that is filled with standard issue salt bought at a standard supermarket. NaCl with 31mg fluoride and 2 mg of iodine per 100 grams of salt (just looked at the package). Nothing else.

Definitely something else.

Neither iodine nor fluoride can substantially alter the shape of salt crystals. But after a little research, I found that there's something commonly added to salt that does. Glycine is added to reduce "caking" by distorting the natural cubic crystals.

Glycine (NH2CH2COOH) affects salt crystal growth dramatically by causing edges not to form at all (near spherical "blobby" crystals) or having edges and corners spawn less acute edges, which is how you end up with cuboctehedrons. This eliminates large faces that can provide sufficient surface area for crystals to fuse.

Now, glycine supplements have been linked to anxiety, but that's in dosages measured in grams, so you probably don't have to worry about a mg or two in your 2000mg daily dose of salt.

Thanks for that info!

You're quite welcome.

I re-checked and have to admit that under another heading a fourth ingridient was listed, and that is sodium ferrocyanide (Na4[Fe(CN)6]). It is used as anticaking agent in the EU (known as E535),

Yep, same effect. Alters the way the salt recrystalizes.

and it is allowed to put up to 20 mg sodium ferrocyanide into 1 kg of salt. It is toxic for kidneys, but not in the low dosage used here. A man weighing 75 kg would have to ingest 165 grams salt in one day to cross the toxicity treshold of 4.4mg/kg weight (NOAEL).

Fun. The thing to worry about is kids, who have a fraction of adult body weight + a tendency to eat large quantities of fairly random things. Oh, and of course TikTok challenges. Salt should still be a lot safer than Tide pods.

How do kids survive to become adults. I remember things from my childhood that should have prevented survival...

It looks like that magnified - AFAIK it's ground, so that may explain the shapes it shows here.

It doesn't. You can see some grinding damage on some of the crystals, especially in the second shot, but it's not severe. You can't really grind crystals into spheres without controlled grinding of each crystal on a faceting machine, and even then, they tend to accumulate damage on natural cleavage planes.

Interesting to know ...

Thanks. I try.

You've got full-blown weird "grown" shapes.

I presume that the sodium ferrocyanide might be responsible for that then?

There's only three ways to prevent caking. Altering crystal shapes, lubricating the crystals, and adding a desiccating agent. Only altering the crystal shapes is cheap in mass quantities.

Food safety is pretty tight here in the EU, and I'm pretty sure that nothing illegal is being done in standard supermarket fare (or if it was being done at least it wouldn't stay unknown for too long ...).

Anyway thanks for taking the time and doing that research. Most interesting and enlightening!

You're welcome.

Thank you for raising such an interesting subject.